Polyester resins such as polyethylene terephthalate(hereinafter referred to as “PET”) have good heat resistance, processability and transparency, and non-toxicity compared with other materials, and, therefore are widely used for daily products and industrial supplies. Accordingly, a demand for polyester resins and production of that is increasing continuously and the polyester resin wastes also increase. As a result, environmental problems are looming large, concerning the treatment of these wastes. These polyester resin wastes are specified as recyclable in Korean Wastes Control Act but only a little amount of them is recycled, because the technological level of recycling method is merely to remelt physically the waste polyester resins, and make products and the quality of the reclaimed products is not satisfactory. Thus, treatment of the waste polyester resins becomes a serious problem, and methods for solving this problem are required desperately.